1. Field of the Invention
This invention relates to the production of dietetic dog biscuits. In particular, this invention relates to dietetic dog biscuits containing vegetable hulls which are used to selectively balance the nutritional composition of the biscuit and make the biscuit low in calories, low in total protein, high in essential amino acids, high in fiber, or a combination of these.
2. Description of the Prior Art
Many pet owners are concerned with the nutritional needs of their pets. To meet nutritional requirements, pet food formulas can be selectively altered to vary the protein content, vitamin and mineral content, and caloric content. The altering of these ingredients when making a canned or "wet" pet food product has little effect on the texture and flavor of the pet food. The balance of these ingredients becomes more critical when making a dry food because a portion of the formula must be structural ingredients such as starch containing flours which are required to form a pellet. When making a dog biscuit pet food, the requirement that a portion of the formula be for structural ingredients becomes even more critical. Structural ingredients or gluten and starch containing flours form the dough matrix within a biscuit and maintain the texture and hardness of the biscuit after baking. Altering the nutritional ingredients in a biscuit formula can have an adverse effect on a biscuit. The alteration of these ingredients can effect the color, biscuit strength, the rise of the biscuit, and the hardness of the biscuit.
Common dog biscuits typically contain between about 60 to about 70 percent wheat flour, 10 percent soybean meal, 6 percent meat and bone meal, between 2 and 3 percent animal fat such as tallow, and 11 to 12 percent miscellaneous ingredients. These biscuits usually contain about 1.5 percent fiber and about 360 to 385 calories per 100 grams of biscuit. Typically dog biscuits contain between 20 and 22 percent protein. The majority of this protein is derived from the wheat flours used to make the dog biscuit.
The substitution of a portion of the wheat flour with other ingredients in a dog biscuit can be done to accomplish a variation in the protein content or caloric content of the dog biscuit. The substitution of wheat flour with a farinaceous flour can be useful in reducing the protein content of the dog biscuit, but might not sufficiently reduce a caloric content of the dog biscuit. Inert ingredients can be used as substitutes for wheat flour to reduce the caloric content of a dog biscuit. In either case, substitution of wheat flour in a biscuit formula creates problems in the manufacturing of the dog biscuit such adverse alterations to the texture and appearance of the final product which effect consumer acceptance of the product.
The problems that occur in manufacturing and baking dog biscuits with decreased wheat flour content include texture problems, undesirable color variations, and biscuit strength problems. The texture of dog biscuits is important to the product because biscuits are very useful in cleaning a dog's teeth. A texture that is too soft or too brittle does not provide enough abrasive action for cleaning the animal's teeth or does not conform to the tooth surface during chewing. It is often desirable that the texture of dog biscuits intended for older or "senior" dogs provide a softer chew. Undesirable color variations in a dog biscuit often do not alter the acceptability of the biscuits to the animal, but color variations are important to the animal's owner. Acceptance of the product by the animal's owner is increased when the biscuit has a healthy, appetizing appearance. A rich brown, but not dark, color is desirable to most pet owners purchasing dog biscuits. A biscuit which is too light in color or white does not appear cooked. A biscuit that is too dark in color appears "burned". Problems with biscuits are encountered when too much gluten containing wheat flour is removed from a biscuit formula and replaced with ingredients that do not aid in the development and strength of the biscuit dough. Such ingredients include fish meal, corn flour, and inert fibers. A decrease in the strength of the biscuit can lead to difficulties in the manufacturing of the biscuit, particularly during the forming of the biscuits.
U.S. Pat. No. 4,310,558 to Nahm discloses a formula to produce extruded pellets providing a balance of protein for adult dogs. The protein is balanced by mixing proteinaceous and farinaceous grains. Specifically, proteinaceous wheat flour is mixed with farinaceous flour such as corn flour. This patent also uses fish meal to give a more suitable protein combination not obtained with formulas containing only flour. The fish meal is added to increase the essential amino acids which are provided in high enough quantities by the flours alone. This patent is concerned with extrusion cooking of pellets as opposed to producing a biscuit.
An example of substitute ingredients for wheat flour is found in U.S. Pat. No. 3,365,297 to Burgess which discloses a method of making animal food, in this case pellets as opposed to biscuits, in which proteinaceous and farinaceous meals are combined. This mixture contains wheat, corn, meat, soy, and fish meal. The object of this invention is to produce food pellets that retain their particulate character upon hydration. The use of cold water in this patent is to effect pyrolysis of the starches. This patent does not involve the making of a nutritionally balanced, low calorie, dietetic biscuit.
U.S. Pat. No. 3,708,306 to Appleman reveals an animal food product combining various grains with corn flour and fish meal. Appleman is directed to the production of biscuits having a desirable color, protein enrichment, and a softer chew. This patent, however, is primarily directed at the use of psyllium flour in animal foods.
U.S. Pat. No. Des. 982,711 to Ellis discloses a biscuit with a stylized appearance of a bone. This patent reveals the use of gluten flour and corn meal together with other products in the making of the biscuit. This patent discusses the effect that this mixture has on the final color of the patent. The disclosure in this patent is not directed to producing a low calorie dietetic biscuit.
U.S. Pat. Nos. 2,827,377 to Frost, 3,438,780 to Singer, 4,212,896 to Brown, and 4,371,556 to Pitchon are each directed at the production of animal feed containing corn meal combined with another grain. The Frost patent is primarily concerned with the production of improved feed for poultry. Its formula uses corn meal with fish by-products to obtain a nutritious balance. The Singer patent is concerned with an improved process for making animal feed in which corn and wheat meals are combined. The Brown patent discloses numerous formulas including corn meal with other grains, all of which include molasses. The inclusion of molasses with various cereal products yields a chewy non-crumbly structure. The Pitchon patent includes a discussion of farinaceous and proteinaceous ingredients. This patent is primarily concerned with the inclusion of soy products in a palatable dog food.
Less active adult and senior dogs do not usually need as many calories as do younger dogs. It is desirable that low calorie biscuits intended for consumption by senior dogs provide a nutritionally balanced diet. A low calorie product must satisfy the animal's appetite. To provide a biscuit which is satisfying, but low in calories, a portion of the wheat flour used to make the biscuit must be removed and substituted with nonfunctional ingredients which are low in calories.
U.S. Pat. No. 4,287,220 to Pappas et al. discloses an essentially solid, free-flowing, blended composition containing cooked farinaceous food products and one or more of rice hulls or soybean hulls and peanut hulls. Other dietary solids such as cellulose fibers can be included as an inert ingredient. This patent concerns the preparation of an animal feed from products derived from waste by-products in food manufacturing operations. This patent does not concern the use of rice hulls or other waste products in the manufacturing of a biscuit. This disclosure is directed at animal feed compositions which are mixed, blended, and the bagged.
U.S. Pat. No. 3,767,423 to Tsantir et al. discloses a low calorie bread which is prepared by replacement of a portion of the flour used in the dough by a mixture of finely divided edible hulls of vegetable origin. Rice hulls and soybean hulls are designated as suitable ingredients for this purpose. This reference is concerned with the production of a bread containing a combination of hulls which are substituted for starch ingredients and reduce the calories of the bread. The formulas and examples disclose a bread which is smooth, light, and resilient in texture. This patent states in column 1 that the applicants are aware of non-nutritive food substances including, among other things, rice hulls, having been proposed for use separately, but not in conjunction with one another in making biscuits or crackers. No specific examples are given. This disclosure does not lead one to a suitable formula or method for incorporating rice hulls into a biscuit intended for animal consumption wherein the biscuit is nutritionally balanced and provides a concentration of rice hulls or other hulls which reduces the calories of the biscuit and provides a texture with teeth cleaning qualities during consumption.
U.S. Pat. No. 2,745,748 to McCashen discloses a process for making whole grained flours. The flours can be made from numerous identified cereal grains which have hulls attached to the starch of the flour. This patent is not concerned with the utilization of rice hulls or other vegetable hulls to reduce the caloric content of a dog biscuit.
U.S. Pat. No. 4,431,674 to Fulger et al. discloses a process for producing an all natural, enzyme-saccharide cereal derived from whole grain. This patent discusses the use of numerous cereal grains. The claimed process involves milling the whole cereal grain, which would include portions of the hull. Rice is identified as a cereal grain which can be used to make a cereal according to this patent. This patent is unconcerned with producing a baked dog biscuit which is reduced in calories and nutritionally balanced.
United Kingdom Pat. No. 290 811 discloses a pet food containing a balance of farinaceous and proteinaceous material. The pet food according to this invention contains a starch conditioner which is used to stabilize the moisture content of the food product. This patent is unconcerned with the production of a baked dog biscuit, but does disclose a formula containing soy hulls intended for use in a dog food made according to the claims of this patent.
The prior art does not disclose a formula nor process to produce dietetic dog biscuits for adult or older dogs in which the standard wheat flour content of the biscuit has been substituted in part by vegetable hulls to alter the balance of the biscuit's protein, fiber, caloric content, or combination of these properties. This invention provides a nutritionally balanced, dietetic dog biscuit which can be low in calories. This invention provides a product and its process to manufacture dog biscuits that are nutritionally balanced and contain vegetable hulls.